The A000110 shield features four relays that support any 3.3 V and 5 V
Arduino board with the driving of high current loads. Each of the relays
provides 2 pole changeover contacts (NO and NC) and have an LED for
on/off status. The shield relies on the Arduino board for power. Arduino
board pins control the four relays. You can also interface various Tinkerkit
modules to the shield via the shield Tinkerkit I/O and communications
interfaces to add functionality to your design. For protection, the
shield can be attached to a case/enclosure with four screws.

Technical

Features

4 units of relays module compatible with Arduino Uno. Originally created by Arduino.